Microwave Background Anisotropies and Nonlinear Structures I. Improved Theoretical Models

Abstract

A new method is proposed for modelling spherically symmetric inhomogeneities in the Universe. The inhomogeneities have finite size and are compensated, so they do not exert any measurable gravitational force beyond their boundary. The region exterior to the perturbation is represented by a Friedmann-Robertson-Walker (FRW) Universe, which we use to study the anisotropy in the cosmic microwave background (CMB) induced by the cluster. All calculations are performed in a single, global coordinate system, with nonlinear gravitational effects fully incorporated. An advantage of the gauge choices employed here is that the resultant equations are essentially Newtonian in form. Examination of the problem of specifying initial data shows that the new model presented here has many advantages over `Swiss cheese' and other models. Numerical implementation of the equations derived here is described in a subsequent paper.

10 pages, 4 figures; Monthly Notices of the Royal Astronomical Society (MNRAS), in press

References in corpus (3)

• Gravity, Gauge Theories and Geometric Algebra
• Detection of a Small Scale Cosmic Background Anisotropy at 3.6 cm
• Secondary gravitational anisotropies in open universes

Cited by in corpus (7)

• A new form of the Kerr solution
• Secondary anisotropies of the CMB
• Full-sky map of the ISW and Rees-Sciama effect from Gpc simulations
• Did WMAP see Moving Local Structures?
• An alternative approach to modelling a cosmic void and its effect on the cosmic microwave background
• Dynamics of a spherical object of uniform density in an expanding universe
• Microwave background anisotropies due to non-linear structures in open and Lambda universes